11665591 has 8 divisors (see below), whose sum is σ = 13372704. Its totient is φ = 9968640.

The previous prime is 11665573. The next prime is 11665597. The reversal of 11665591 is 19556611.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 11665591 - 2⁷ = 11665463 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11665597) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 111 + ... + 4831.

It is an arithmetic number, because the mean of its divisors is an integer number (1671588).

Almost surely, 2^11665591 is an apocalyptic number.

11665591 is a deficient number, since it is larger than the sum of its proper divisors (1707113).

11665591 is an equidigital number, since it uses as much as digits as its factorization.

11665591 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5081.

The product of its digits is 8100, while the sum is 34.

The square root of 11665591 is about 3415.4927902134. The cubic root of 11665591 is about 226.7960999032.

The spelling of 11665591 in words is "eleven million, six hundred sixty-five thousand, five hundred ninety-one".